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User Information
Maintaining the Instrument
If there are are no bubbles or a slow stream of bubbles, call an
Agilent service representative. The Headspace Sampler may
have the following problems:
•
Plugged or restricted vent flow paths
•
Plugged or restricted valves
•
Leak in the vent flow path
Pressure decay test
Overview
Each pressure decay test has four steps:
1
Pressurize the flow path long enough for the pressure to
equalize across manual pneumatic controls and the flow
restrictor.
2
Seal the flow path.
3
Monitor the pressure for 5 minutes.
4
Check the results. The pressure should decay less than 2 psi
over 5 minutes.
The pressure decay test is normally done twice:
•
Once with the sampling loop in the vial pressurization
flowpath (standby mode)
•
Once with the sampling loop in the carrier flow path (inject
mode).
An optional pressure decay test checks for leaks across the
6-port valve. This optional test requires up to four additional
pressure decay tests.
medium_standard.book Page 150 Tuesday, February 17, 2004 10:14 AM
